Fluid sterilization plays an important role across a wide spectrum of applications, to include personal, industrial, manufacturing, and medical applications. Generally speaking, sterilization is identified as a process that will make an object free of any living transmissible agent (such as fungi, bacteria, viruses, spore forms, microorganisms, prions, etc.). The object to be sterilized may be any of several types, including surfaces, a volume of fluid, or other materials in use or to be used in human or animal activities. Effectiveness of sterilization is generally referenced via a sterility assurance level (SAL).
Moreover, the issue of aqueous fluid sterilization is one of growing importance to both the developed and developing world alike. Complications resulting from contact with bacterially contaminated water are some of the leading causes of illness in the developing world. Further, it is one of the leading causes of death amongst children in the developing world.
Current challenges embodied in present sterilization operations of water leave much room for improvement. Most clean water systems today use sterilization processes such as reverse osmosis, membrane (filter) technology, or UV light technology. These systems require regular maintenance, a large amount of energy, and routine replacement of major components, such as membranes, filters or UV bulbs. As such, they are expensive to operate and maintain, particularly for high volume applications. Another solution involves the heating of the water to a high temperature as a means to sterilize, which typically requires large heat-sink apparatus to contain and cool the water after heating.
Both approaches necessitate the apparatus to be structurally large and generally immobile. Further challenges involve solutions using a non-continuous flow of the fluid, by-product being created by the process necessitating more maintenance, and the limitation to process only water.
Additionally, as invasive medical procedures become more commonplace and routine, the growing contact of foreign instruments with the relatively unprotected interior of human bodies greatly increases the need of proper instrument sterilization. Current solutions typically involve sterilization through immersion in disinfecting solutions (e.g., alcohol or bleach), ultrasonic methods (produce cavitation via high frequency sound waves) to clean, or exposure to high temperature in the form of high-pressure steam. These solutions have their limiting challenges: disinfecting solution methods produce harmful waste with limited re-use; the ultrasonic process is time intensive and demanding of both energy and maintenance; and high-pressure steam solutions can potentially damage sensitive and fragile equipment and special equipment with high pressure seals, etc. Most current solutions contain a number of moving parts, the addition of each creating the added issue of maintenance, and risk of possible contamination.
Further, contaminants such as “prions” are very difficult to kill and resistant to virtually all current sterilization methods. Prions are proteins that are folded in structurally distinct ways, which can be transmissible to other proteins, causing these other protein molecules to adopt such distinctive folding. Such misfolded protein replication within humans and other mammals can be harmful, particularly to brain and nervous tissue. This form of replication leads to disease that is similar to viral infection.
A protein as an infectious agent stands in contrast to all other known infectious agents, like viruses, bacteria, fungi, or parasites—all of which must contain nucleic acids (DNA, RNA, or both). In many instances, prions in mammals can have deleterious consequences, such as damage to brain and neural tissue, which are currently untreatable, other than complete removal of the infected tissue from the patient. Equipment and instruments used for such treatment must thereafter be considered contaminated.
Current procedures for decontaminating medical equipment are ineffective at reliably eliminating or inactivating prions to a medically acceptable level. As such, current protocols commonly call for disposal and destruction of medical equipment exposed to prions, which is an expensive proposition.
In yet other applications, ocean ships and other water vessels employ ballast tanks that may intake water from one port, and subsequently discharge the water in another port, for stabilization of the vessel, wherein such stabilization can be a function of the weight onboard, and can take into account weight fluctuations, for e.g. due to the loading/unloading of cargo. However, discharging water collected from a foreign port into a local port can potentially introduce foreign biological matter into the ecosystem of the local body of water, thereby harming its vitality. As such, governing agencies across the world, including the U.S. Coast Guard for the United States have established a sterilization level that must be adhered for all water vessels discharging such water within the ballast tanks. Although current methods exist to achieve this level of sterilization, such as using UV light, such methods can be inefficient, and sometimes ineffective particularly when targeting large microorganisms.
Therefore, it should be appreciated there remains a need for an apparatus and method which can produce sterile fluid for a variety of uses, such as, to sterilize contaminated instruments and equipment to a degree not possible with current approaches.